This invention relates to thermoplastic polyethers having pendant hydroxyl moleties and to methods of using them as barrier articles to protect oxygen-sensitive materials.
Hydroxyphenoxyether polymers are known to be useful in the fabrication of articles exhibiting barrier properties. See, for example, Reinking et al., J. Poly. Sci., Vol. 7, pp. 2135-2144, pp. 2145-2152 and pp. 2153-2160 (1963) and Encyclopedia of Polymer Science and Technology, Vol. 10, pp. 111-122. Such polymers generally have only moderate oxygen barrier, i.e., they generally exhibit oxygen transmission rates of 2 to 75 cm.sup.3 -mil/100 in.sup.2 -atm(O.sub.2)-day.
In view of the limited barrier properties of the prior art polymers having pendant hydroxyl moieties and phenoxyether moieties, it would be highly desirable to provide a polymer having a high barrier to oxygen (i.e., oxygen transmission rate less than 20 cm.sup.3 -mil/100-in.sup.2 -atm(O.sub.2)-day). Polymers that retain such high barrier in both dry and moist environments and can be fabricated into flexible films would be especially desirable.